1. Field of the Invention
The present invention relates to a structure of valve stem and frame lining.
2. Description of the Prior Art
Tires are inflated by filled with gas usually via valve stems disposed on wheel frames. Conventional valve stems are usually employed for tires with inner tubes, as disclosed in patents TW 510315, TW M289391, TW M414521, and TW M355175. Air rooms of tires with inner tubes are closed and have little problem of air-leakage. However, if the valve stems disclosed in the patents mentioned above are employed for tires without inner tube, air-leakage may easily happen.
Even though rubber enhancement pieces are formed on the bottom of valve stems in foregoing patents, the enhancement pieces can only be disposed on inner tubes or tubular tires. Valve stems of tires without inner tubes are disposed on wheel frames, so some through holes should be formed on wheel frames to receive valve stems. However, the wheel frames are made of hard materials, so that it is not convenient that the holes on the wheel frames possibly result air-leakage.
Besides, a valve stem for a tire without inner tube is disclosed in patent U.S. Pat. No. 6,119,746. However, the wheel frame should form two holes every valve stem, and only one O-ring is disposed between the each hole and the valve stem. Moreover, there is no anti-leakage measure between the outer cover and the wheel frame. Thus, air-leakage is highly possible to happen.
The present invention is, therefore, arisen to obviate or at least mitigate the above mentioned disadvantages.